hw/ppc: use g_free() in spapr_tce_table_post_load()

tcet->mig_table is copied from tcet->table, which in turn is created
in spapr_tce_alloc_table() using g_new0().

Use g_free() instead of free() to deallocate it.

Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
[Mjt: fix commit comments]
diff --git a/hw/ppc/spapr_iommu.c b/hw/ppc/spapr_iommu.c
index 63e34d4..5e3973f 100644
--- a/hw/ppc/spapr_iommu.c
+++ b/hw/ppc/spapr_iommu.c
@@ -248,7 +248,7 @@
         memcpy(tcet->table, tcet->mig_table,
                tcet->nb_table * sizeof(tcet->table[0]));
 
-        free(tcet->mig_table);
+        g_free(tcet->mig_table);
         tcet->mig_table = NULL;
     }